A mixture of gaseous CO and H2, called synthesis gas, is used commercially to prepare methanol (CH3OH), a compound considered an alternative fuel to gasoline. Under equilibrium conditions at 540.2 K, [H2] = 0.067 mol [CO]=0.021 mol/L and [CH3OH]=0.040 mol/L what is the value of Kc for this reaction at 505.0 K?

Answer : The value of equilibrium constant (K) is, 424.3

Explanation :  Given,

Concentration of at equilibrium = 0.067 mol

Concentration of at equilibrium = 0.021 mol

Concentration of at equilibrium = 0.040 mol

The given chemical reaction is:

The expression for equilibrium constant is:

Now put all the given values in this expression, we get:

Thus, the value of equilibrium constant (K) is, 424.3

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.